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1.
Braz. j. biol ; 84: e251438, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345560

RESUMO

Abstract The northwestern portion of the Upper Paraná Atlantic Forest ecoregion is one of the most disturbed and fragmented areas in the Atlantic Forest, and little is known about the local avifauna. In this study, we have described the composition and diversity of the aquatic avifauna of this region and analyzed the patterns of similarity with respect to the seasonal as well as spatial distribution. We used the line transect sampling technique in six distinct humid areas (including lentic and lotic water bodies) during the dry and rainy seasons of 2012 and 2013. A total of 52 species of waterfowl were recorded. The species richness of the studied areas was surprisingly distinct; only seven waterfowl species, namely Cairina moschata (Linnaeus, 1758), Tigrisoma lineatum (Boddaert, 1783), Rosthramus sociabilis (Vieillot, 1817), Aramus guarauna (Linnaeus, 1766), Vanellus chilensis (Molina, 1782), Jacana jacana (Linnaeus, 1766), and Arundinicola leucocephala (Linnaeus, 1764), were common to these six studied areas. This indicated that the other bird species that were observed might be habitat selective. Moreover, the analysis of the composition of birds in the two seasons (dry and rainy) combined with their spatial distributions showed significant dissimilarities between the areas with lotic (river and constructed wetland) and lentic (lagoons) characteristics. Nevertheless, despite the small extent and low total richness of the entire study area, it was found to be home to 1/3 of all freshwater aquatic birds documented in the state of São Paulo, with the record of 5 migratory species and 11 new species added to the northwest of the state. The heterogeneity of local aquatic environments, habitat selection combined with seasonality, and the absence of other humid locations in the surroundings can explain the diversity and distribution of these birds in the water bodies of this uninvestigated Atlantic Forest ecoregion.


Resumo A porção noroeste da ecorregião Floresta Atlântica do Alto Paraná é uma das mais alteradas e fragmentadas da Mata Atlântica, da qual pouco se sabe sobre a avifauna local. Nosso objetivo foi descrever a diversidade e composição da avifauna aquática, bem como analisar os padrões de similaridade quanto a distribuição temporal e espacial destas aves nesta ecorregião. Utilizamos a transecção linear para amostragem em seis áreas úmidas (corpos d'água lênticos e lóticos), nos períodos de seca e chuva entre 2012 e 2013. Registramos 52 espécies de aves aquáticas e as riquezas das áreas mostraram-se distintas, pois apenas Cairina moschata (Linnaeus, 1758), Tigrisoma lineatum (Boddaert, 1783), Rosthramus sociabilis (Vieillot, 1817), Aramus guarauna (Linnaeus, 1766), Vanellus chilensis (Molina, 1782), Jacana jacana (Linnaeus, 1766), and Arundinicola leucocephala (Linnaeus, 1764) foram comuns às seis áreas, o que indica seleção de habitat. Quando analisada a composição das aves nos dois períodos aliada à distribuição espacial, encontramos dissimilaridades temporais acentuadas entre os ambientes com características lóticas (rio e aterro) e lênticas (lagoas). Isto mostra que, além das diferentes épocas sazonais, é necessário analisar separadamente os diferentes tipos de áreas úmidas. Por fim, apesar da extensão pequena e baixa riqueza total, a área amostrada abrigou 1/3 das aves aquáticas de água doce para o estado de São Paulo, cinco espécies migratórias e 11 novas espécies para o noroeste do estado. A heterogeneidade de ambientes aquáticos locais, forte seleção de habitat aliada à sazonalidade e ausência de outros locais úmidos em seu entorno, explicam a diversidade e distribuição destas aves estreitamente relacionadas aos corpos d'água desta desconhecida ecorregião da Mata Atlântica.


Assuntos
Animais , Aves , Biodiversidade , Estações do Ano , Brasil , Florestas , Ecossistema
2.
Braz. j. biol ; 84: e255055, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355865

RESUMO

Abstract This study was aimed to investigate Carbofuran (CF)-induced pathological changes in cattle egret. Two hundred cattle egrets were reared and equally divided into four groups and given different CF concentrations (0.03 mg/L, 0.02 mg/L, 0.01 mg/L and 0 mg/L (control group)). Hematology, serum biochemistry, histopathology, and immunological markers were studied. Our results confirm that CF induces anemic conditions, leukocytosis, elevated liver enzymatic activity, and alterations in renal biomarkers. Moreover, specific microscopic lesions such as multifocal necrosis, pyknotic nuclei, hemorrhages, congestion, and inflammatory cell proliferation were observed in the liver, kidney, spleen, and thymus. These findings suggest that CF can induce harmful effects, so the application of this pesticide in the field must be strictly monitored to mitigate the possibility of exposure to non-target species.


Resumo Este estudo teve como objetivo investigar as alterações patológicas induzidas por carbofurano (CF) em garças-vaqueiras. Duzentas dessas garças foram criadas e divididas igualmente em quatro grupos e receberam diferentes concentrações de CF: 0,03 mg/L; 0,02 mg/L; 0,01 mg/L; e 0 mg/L (grupo controle). Foram realizadas análises de hematologia, bioquímica sérica, histopatologia e marcadores imunológicos. Nossos resultados confirmaram que CF induz condições anêmicas, leucocitose, atividade enzimática hepática elevada e alterações nos biomarcadores renais. Além disso, lesões microscópicas específicas, como necrose multifocal, núcleos picnóticos, hemorragias, congestão e proliferação de células inflamatórias, foram observadas no fígado, rim, baço e timo. Esses achados sugerem que o CF pode causar efeitos nocivos, portanto a aplicação desse agrotóxico no campo deve ser rigorosamente monitorada para mitigar a possibilidade de exposição a espécies não alvo.


Assuntos
Animais , Carbofurano/toxicidade , Aves , Bovinos
3.
Braz. j. biol ; 84: e250280, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355867

RESUMO

Abstract Endozoochory by waterbirds is particularly relevant to the dispersal of non-flying aquatic invertebrates. This ecological function exercised by birds has been demonstrated in different biogeographical regions, but there are no studies for the neotropical region. In this work, we identified propagules of invertebrates in faeces of 14 syntopic South American waterbird species representing six families, and hatched additional invertebrates from cultured faeces. We tested whether propagule abundance, species richness and composition varied among bird species, and between the cold and warm seasons. We found 164 invertebrate propagules in faecal samples from seven different waterbirds species, including eggs of the Temnocephalida and Notonectidae, statoblasts of bryozoans (Plumatella sp.) and ephippia of Cladocera. Ciliates (including Paramecium sp. and Litostomatea), nematodes and rotifers (Adineta sp. and Nottomatidae) hatched from cultured samples. Potential for endozoochory was confirmed for 12 of 14 waterbird species. Our statistical models suggest that richness and abundance of propagules are associated with bird species and not affected by seasonality. Dispersal by endozoochory is potentially important to a broad variety of invertebrates, being promoted by waterbirds with different ecological and morphological traits, which are likely to drive the dispersal of invertebrates in neotropical wetlands.


Resumo A endozoocoria promovida por aves aquáticas é particularmente relevante para a dispersão de invertebrados aquáticos não-voadores. Essa função ecológica exercida pelas aves tem sido demonstrada para diferentes regiões biogeográficas, porém, não existem estudos para a região neotropical. Neste trabalho nós identificamos propágulos de invertebrados encontrados em fezes de 14 espécies sintópicas de aves aquáticas da América do Sul, representando seis famílias de aves, e também invertebrados emergidos de amostras fecais cultivadas em laboratório. Testamos se a abundância, riqueza de espécies e composição de propágulos de invertebrados variavam entre as espécies de aves e entre estações. Nós encontramos 164 propágulos de invertebrados em amostras fecais de sete espécies de aves, incluindo ovos de Temnocephalida e Notonectidae, estatoblastos de briozoários (Plumatella sp.) e efípios de Cladocera. Ciliados (incluindo Paramecium sp. e Litostomatea), nematóides e rotíferos (Adineta sp. e Nottomatidae) eclodiram de amostras cultivadas. O potencial para endozoocoria foi confirmado para 12 das 14 espécies de aves aquáticas investigadas. Nossos modelos estatísticos sugerem que a riqueza e abundância de propágulos estão associadas às espécies de aves e não são afetadas pela sazonalidade. A dispersão por endozoocoria é importante para uma ampla variedade de invertebrados, sendo promovida por aves aquáticas com diferentes características ecológicas e morfológicas as quais provavelmente regulam a dispersão de invertebrados entre áreas úmidas neotropicais.


Assuntos
Humanos , Animais , Áreas Alagadas , Invertebrados , Estações do Ano , Aves
4.
Braz. j. biol ; 84: e256160, 2024. tab, graf, mapas, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360203

RESUMO

Riverine forests are unique and highly significant ecosystems that are globally important for diverse and threatened avian species. Apart from being a cradle of life, it also serves as a gene pool that harbors a variety of flora and fauna species (repeated below). Despite the fact, this fragile ecosystem harbored avian assemblages; it is now disappearing daily as a result of human activity. Determining habitat productivity using bird species is critical for conservation and better management in the future. Multiple surveys were conducted over a 15-month period, from January to March 2019, using the distance sampling point count method. A total of 250 point count stations were fixed systematically at 300 m intervals. In total, 9929 bird individuals were recorded, representing 57 species and 34 families. Out of 57 bird species, two were vulnerable, one was data deficient, one was nearly threatened, and the remaining 53 species were of least concern. The Eurasian Collard Dove - Streptopelia decaocto (14.641 ± 2.532/ha), White-eared Bulbul - Pycnonotus leucotis (13.398 ± 4.342/ha) and Common Babbler - Turdoides caudata (10.244 ± 2.345/ha) were the three first plenteous species having higher densities. However, the densities of three species, i.e., Lesser Whitethroat - Sylvia curruca, Gray Heron - Ardea cinerea and Pallas Fish Eagle - Haliaeetus leucoryphus, were not analyzed due to the small sample size. The findings of diversity indices revealed that riverine forest has harbored the diverse avian species that are uniformly dispersed across the forest. Moreover, recording the ten foraging guilds indicated that riverine forest is rich in food resources. In addition, the floristic structure importance value index results indicated that riverine forest is diverse and rich in flora, i.e. trees, shrubs, weeds and grass, making it an attractive and productive habitat for bird species.


As florestas ribeirinhas são ecossistemas únicos e altamente significativos que são globalmente importantes para diversas espécies de aves ameaçadas de extinção. Além de serem o berço da vida, também servem como um conjunto genético que abriga uma variedade de espécies da flora e da fauna. Apesar disso, esse frágil ecossistema abrigava um conjunto de aves, mas agora está desaparecendo diariamente como resultado da atividade humana. Determinar a produtividade do hábitat usando espécies de pássaros é fundamental para a conservação e melhor gestão no futuro. Vários levantamentos foram realizados ao longo de um período de 15 meses, de janeiro de 2018 a março de 2019, por meio do método de contagem de pontos de amostragem de distância. Foram fixadas sistematicamente 250 estações de contagem de pontos em intervalos de 300 m. No total, foram registrados 9.929 indivíduos de aves, representando 57 espécies e 34 famílias. Das 57 espécies de aves, duas eram vulneráveis, uma tinha dados insuficientes, uma estava quase ameaçada e as 53 espécies restantes eram as menos preocupantes. O: Pomba de colar euroasiática - Streptopelia decaocto (14.641 ± 2.532/ha), o Bulbul de orelha branca - Pycnonotus leucotis (13.398 ± 4.342/ha) e Tagarela comum - Turdoides caudata (10.244 ± 2.345/ha) foram as três primeiras espécies abundantes com maiores densidades. No entanto, as densidades de três espécies, Papa-amoras-cinzento (Sylvia curruca), Garça-real-europeia (Ardea cinerea) e Águia-pescadora de Pallas (Haliaeetus leucoryphus), não foram analisadas por causa do pequeno tamanho da amostra. Os resultados dos índices de diversidade revelaram que a floresta ribeirinha abrigou diversas espécies de aves que estão uniformemente dispersas pela floresta. Além disso, o registro das dez guildas de forrageamento indicou que a floresta ribeirinha é rica em recursos alimentares. Além disso, os resultados do índice de valor de importância da estrutura florística indicaram que a floresta ribeirinha é variada e rica em flora, ou seja, árvores, arbustos, ervas daninhas e grama, tornando-a um hábitat atraente e produtivo para espécies de aves.


Assuntos
Aves , Florestas , Ecossistema , Patrimônio Genético
6.
Proc Biol Sci ; 290(1995): 20230160, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36919426

RESUMO

Skeletal pneumaticity is a key feature of extant avian structure and biology, which first evolved among the non-flying archosaurian ancestors of birds. The widespread presence of air-filled bones across the postcranial skeleton is unique to birds among living vertebrates, but the true extent of skeletal pneumaticity has never been quantitatively investigated-hindering fundamental insights into the evolution of this key avian feature. Here, we use microCT scans of fresh, frozen birds to directly quantify the fraction of humerus volume occupied by air across a phylogenetically diverse taxon sample to test longstanding hypotheses regarding the evolution and function of avian skeletal pneumatization. Among other insights, we document weak positive allometry of internal air volume with humeral size among pneumatized humeri and provide strong support that humeral size, body mass, aquatic diving, and the presence or absence of pneumaticity all have independent effects on cortical bone thickness. Our quantitative evaluation of humeral pneumaticity across extant avian phylogeny sheds new light on the evolution and ontogenetic progression of an important aspect of avian skeletal architecture, and suggests that the last common ancestor of crown birds possessed a highly pneumatized humerus.


Assuntos
Ar , Evolução Biológica , Aves , Úmero , Animais , Aves/anatomia & histologia , Fósseis/anatomia & histologia , Filogenia , Microtomografia por Raio-X , Úmero/anatomia & histologia , Úmero/diagnóstico por imagem , Osso Cortical/anatomia & histologia , Osso Cortical/diagnóstico por imagem
7.
Proc Biol Sci ; 290(1995): 20222099, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36919431

RESUMO

Daily torpor allows endotherms to save energy during energetically stressful (e.g. cold) conditions. Although studies on avian torpor have mostly been conducted under laboratory conditions, information on the usage of torpor in the wild is limited to few, predominantly temperate-zone species. We studied torpor under seminatural conditions from 249 individuals from 29 hummingbird species across a 1920 m elevational gradient in the western Andes of Colombia using cloacal thermistors. Small birds were more likely to use torpor than large birds, but only at low ambient temperatures, where torpor was prolonged. We also found effects of proxy variables for body condition and energy expenditure on the use of torpor, its characteristics, and impacts. Our results suggest that context-dependency and phylogenetic variation in the probability of deploying torpor can help understand clade-wide patterns of elevational distribution in Andean hummingbirds.


Assuntos
Aves , Metabolismo Energético , Torpor , Animais , Humanos , Aves/fisiologia , Temperatura Baixa , Metabolismo Energético/fisiologia , Filogenia , Torpor/fisiologia , Colômbia , Altitude
8.
Emerg Microbes Infect ; 12(1): 2186608, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36880345

RESUMO

The GsGd lineage (A/goose/Guangdong/1/1996) H5N1 virus was introduced to Canada in 2021/2022 through the Atlantic and East Asia-Australasia/Pacific flyways by migratory birds. This was followed by unprecedented outbreaks affecting domestic and wild birds, with spillover into other animals. Here, we report sporadic cases of H5N1 in 40 free-living mesocarnivore species such as red foxes, striped skunks, and mink in Canada. The clinical presentations of the disease in mesocarnivores were consistent with central nervous system infection. This was supported by the presence of microscopic lesions and the presence of abundant IAV antigen by immunohistochemistry. Some red foxes that survived clinical infection developed anti-H5N1 antibodies. Phylogenetically, the H5N1 viruses from the mesocarnivore species belonged to clade 2.3.4.4b and had four different genome constellation patterns. The first group of viruses had wholly Eurasian (EA) genome segments. The other three groups were reassortant viruses containing genome segments derived from both North American (NAm) and EA influenza A viruses. Almost 17 percent of the H5N1 viruses had mammalian adaptive mutations (E627 K, E627V and D701N) in the polymerase basic protein 2 (PB2) subunit of the RNA polymerase complex. Other mutations that may favour adaptation to mammalian hosts were also present in other internal gene segments. The detection of these critical mutations in a large number of mammals within short duration after virus introduction inevitably highlights the need for continually monitoring and assessing mammalian-origin H5N1 clade 2.3.4.4b viruses for adaptive mutations, which potentially can facilitate virus replication, horizontal transmission and posing pandemic risks for humans.


Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Animais , Humanos , Virus da Influenza A Subtipo H5N1/genética , Raposas , Aves , Canadá/epidemiologia , Mutação , Filogenia
9.
BMJ Paediatr Open ; 7(1)2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36882232

RESUMO

INTRODUCTION: Mother's own breast milk (MOM) is the optimal nutrition for preterm infants as it reduces the incidence of key neonatal morbidities and improves long-term outcomes. However, MOM shortfall is common and either preterm formula or pasteurised donor human milk (DHM) may be used, although practice varies widely. Limited data suggest that the use of DHM may impact maternal beliefs and behaviours and therefore breastfeeding rates. The aim of this pilot study is to determine if longer duration of DHM exposure increases breastfeeding rates, and if a randomised controlled trial (RCT) design is feasible. METHODS AND ANALYSIS: The Human Milk, Nutrition, Growth, and Breastfeeding Rates at Discharge (HUMMINGBIRD) Study is a feasibility and pilot, non-blinded RCT with a contemporaneous qualitative evaluation. Babies born less than 33 weeks' gestation or with birth weight <1500 g whose mothers intend to provide MOM are randomly assigned to either control (DHM used to make up shortfall until full feeds and preterm formula thereafter) or intervention (DHM used for shortfall until 36 weeks' corrected age or discharge if sooner). The primary outcome is breast feeding at discharge. Secondary outcomes include growth, neonatal morbidities, length of stay, breastfeeding self-efficacy and postnatal depression using validated questionnaires. Qualitative interviews using a topic guide will explore perceptions around use of DHM and analysed using thematic analysis. ETHICS APPROVAL AND DISSEMINATION: Nottingham 2 Research Ethics Committee granted approval (IRAS Project ID 281071) and recruitment commenced on 7 June 2021. Results will be disseminated in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ISRCTN57339063.


Assuntos
Aleitamento Materno , Leite Humano , Lactente , Feminino , Recém-Nascido , Animais , Humanos , Projetos Piloto , Alta do Paciente , Aves , Mães , Recém-Nascido de muito Baixo Peso , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Curr Biol ; 33(5): R176-R177, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36917936

RESUMO

Climate change increases the frequency and intensity of extreme weather events that negatively impact wildlife, from individuals to whole ecosystems1. In polar environments, such events include heat waves2, anomalous sea ice concentrations3 and storms4. Polar seabirds are adapted to withstand harsh conditions, and although extreme weather events affect their breeding success and other demographic rates, they are thought to affect only a part of the population. Complete breeding failure of an entire population due to extreme environmental conditions is rarely observed5. Here we report how exceptional storm activity in Dronning Maud Land (DML), Antarctica, in the austral summer of 2021/2022 caused almost complete and large-scale breeding failures of the area's three most common seabird species - Antarctic petrel (Thalassoica antarctica), Snow petrel (Pagodroma nivea) and South polar skua (Stercorarius maccormicki).


Assuntos
Charadriiformes , Ecossistema , Humanos , Animais , Regiões Antárticas , Aves , Cruzamento
11.
Ecol Lett ; 26(4): 609-620, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36855287

RESUMO

Tropical montane communities host the world's highest beta diversity of birds, a phenomenon usually attributed to community turnover caused by changes in biotic and abiotic factors along elevation gradients. Yet, empirical data on most biotic factors are lacking. Nest predation is thought to be especially important because it appears to be common and can change selective pressures underlying life history traits, which can alter competitive interactions. We monitored 2538 nests, 338 of which had known nest predators, to evaluate if nest predation changes along a tropical elevational gradient. We found that nest predation decreased with elevation, reflecting the loss of lowland predators that do not tolerate colder climates. We found different "super" nest predators at each elevation that accounted for a high percentage of events, suggesting that selection pressures exerted by nest predator communities may be less diffuse than has been hypothesized, at least for birds nesting in the understory.


Assuntos
Comportamento de Nidação , Comportamento Predatório , Animais , Aves
12.
Physiol Biochem Zool ; 96(2): 119-127, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36921271

RESUMO

AbstractTorpor, the temporary reduction of metabolic rate and body temperature, is a common energy-saving strategy in endotherms. Because of their small body size and energetically demanding life histories, hummingbirds have proven useful for understanding when and why endotherms use torpor. Previous studies of torpor in hummingbirds have been largely limited to tropical montane species or long-distance migrants that regularly experience challenging thermal conditions. Comparatively little is known, however, about the use of torpor in hummingbirds of the lowland tropics, where relatively high and stable year-round temperatures may at least partially negate the need for torpor. To fill this knowledge gap, we tested for the occurrence of torpor in tropical lowland hummingbirds (n=37 individuals of six species) from central Panama. In controlled experimental conditions simulating the local temperature regime, all six species used torpor to varying degrees and entered torpor at high ambient temperatures (i.e., ≥28°C), indicating that hummingbirds from the thermally stable lowland tropics regularly use torpor. Torpor reduced overnight mass loss, with individuals that spent more time in torpor losing less body mass during temperature experiments. Body mass was the best predictor of torpor depth and duration among and within species-smaller species and individuals tended to use torpor more frequently and enter deeper torpor. Average mass loss in our experiments (∼8%-10%) was greater than that reported in studies of hummingbirds from higher elevation sites (∼4%). We therefore posit that the energetic benefits accrued from torpor may be limited by relatively high nighttime temperatures in the lowland tropics, although further studies are needed to test this hypothesis.


Assuntos
Metabolismo Energético , Torpor , Animais , Regulação da Temperatura Corporal , Temperatura Corporal , Temperatura , Aves
13.
Sci Rep ; 13(1): 4272, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36922555

RESUMO

Telomeres, the nucleotide sequences that protect the ends of eukaryotic chromosomes, shorten with each cell division and telomere loss may be influenced by environmental factors. Telomere length (TL) decreases with age in several species, but little is known about the sources of genetic and environmental variation in the change in TL (∆TL) in wild animals. In this study, we tracked changes in TL throughout the natural lifespan (from a few months to almost 9 years) of free-living house sparrows (Passer domesticus) in two different island populations. TL was measured in nestlings and subsequently up to four times during their lifetime. TL generally decreased with age (senescence), but we also observed instances of telomere lengthening within individuals. We found some evidence for selective disappearance of individuals with shorter telomeres through life. Early-life TL positively predicted later-life TL, but the within-individual repeatability in TL was low (9.2%). Using genetic pedigrees, we found a moderate heritability of ∆TL (h2 = 0.21), which was higher than the heritabilities of early-life TL (h2 = 0.14) and later-life TL measurements (h2 = 0.15). Cohort effects explained considerable proportions of variation in early-life TL (60%), later-life TL (53%), and ∆TL (37%), which suggests persistent impacts of the early-life environment on lifelong telomere dynamics. Individual changes in TL were independent of early-life TL. Finally, there was weak evidence for population differences in ∆TL that may be linked to ecological differences in habitat types. Combined, our results show that individual telomere biology is highly dynamic and influenced by both genetic and environmental variation in natural conditions.


Assuntos
Animais Selvagens , Longevidade , Animais , Animais Selvagens/genética , Longevidade/genética , Aves/genética , Homeostase do Telômero , Encurtamento do Telômero/genética , Telômero/genética
14.
Sci Rep ; 13(1): 4405, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36928348

RESUMO

In the High Arctic, nutrients are the most limiting resources, so terrestrial vegetation is of low complexity and grows slowly. However, locally, large seabird colonies increase soil fertility by deposition of faeces, supporting the development of rich and fast-growing plant communities. Here, we assessed how seabird colonies affected ecological niche segregation of plants, across the fertilisation gradient. Study sites were located near five little auk colonies, distributed longitudinally across the Svalbard archipelago. We described vascular plant composition and identified 13 environmental variables, based on which, we calculated and tested the niche overlap (NO) between the 18 most frequent species. Based on the hierarchical classification of the NO matrix, we distinguished typical High Arctic Vegetation (HAV), and Bird-Cliff Vegetation (BCV). The BCV was characterised by higher average NO and soil δ15N compared to HAV. The highest NO values across the fertilisation gradient were found on the border between the distinguished communities and were positively correlated with species diversity. We suggest that in the High Arctic, seabirds-delivered nutrients lead to the development of separate plant communities through the mechanism of avoiding inter-species competition, while simultaneous high species diversity and NO are related to high facilitation between plants on the border between the communities.


Assuntos
Charadriiformes , Ecossistema , Animais , Regiões Árticas , Aves , Plantas , Solo
15.
Sci Rep ; 13(1): 4361, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36928766

RESUMO

Urbanization affects avian community composition in European cities, increasing biotic homogenization. Anthropic pollution (such as light at night and noise) is among the most important drivers shaping bird use in urban areas, where bird species are mainly attracted by urban greenery. In this study, we collected data on 127 breeding bird species at 1349 point counts distributed along a gradient of urbanization in fourteen different European cities. The main aim was to explore the effects of anthropic pollution and city characteristics, on shaping the avian communities, regarding species' diet composition. The green cover of urban areas increased the number of insectivorous and omnivorous bird species, while slightly decreasing the overall diet heterogeneity of the avian communities. The green heterogeneity-a measure of evenness considering the relative coverage of grass, shrubs and trees-was positively correlated with the richness of granivorous, insectivorous, and omnivorous species, increasing the level of diet heterogeneity in the assemblages. Additionally, the effects of light pollution on avian communities were associated with the species' diet. Overall, light pollution negatively affected insectivorous and omnivorous bird species while not affecting granivorous species. The noise pollution, in contrast, was not significantly associated with changes in species assemblages. Our results offer some tips to urban planners, managers, and ecologists, in the challenge of producing more eco-friendly cities for the future.


Assuntos
Biodiversidade , Ruído , Animais , Cidades , Ruído/efeitos adversos , Melhoramento Vegetal , Aves , Urbanização , Dieta , Ecossistema
17.
Mol Cell ; 83(6): 827-828, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36931253

RESUMO

Osipova et al.1 recently identified an inactivating gene mutation that contributed to the evolution of the hummingbird species by increasing flux of pathways for energy production that are necessary for the unique ability for hovering flight. Lessons from the natural selection for this mutation are applied to physiology and medicine.


Assuntos
Aves , Voo Animal , Animais , Voo Animal/fisiologia , Aves/genética , Aves/metabolismo , Metabolismo Energético/genética , Consumo de Oxigênio , Seleção Genética
18.
J Hazard Mater ; 450: 131090, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36867907

RESUMO

As biota are increasingly exposed to plastic pollution, there is a need to closely examine the sub-lethal 'hidden' impacts of plastic ingestion. This emerging field of study has been limited to model species in controlled laboratory settings, with little data available for wild, free-living organisms. Highly impacted by plastic ingestion, Flesh-footed Shearwaters (Ardenna carneipes) are thus an apt species to examine these impacts in an environmentally relevant manner. A Masson's Trichrome stain was used to document any evidence of plastic-induced fibrosis, using collagen as a marker for scar tissue formation in the proventriculus (stomach) of 30 Flesh-footed Shearwater fledglings from Lord Howe Island, Australia. Plastic presence was highly associated with widespread scar tissue formation and extensive changes to, and even loss of, tissue structure within the mucosa and submucosa. Additionally, despite naturally occurring indigestible items, such as pumice, also being found in the gastrointestinal tract, this did not cause similar scarring. This highlights the unique pathological properties of plastics and raises concerns for other species impacted by plastic ingestion. Further, the extent and severity of fibrosis documented in this study gives support for a novel, plastic-induced fibrotic disease, which we define as 'Plasticosis,'.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Plásticos , Monitoramento Ambiental , Cicatriz , Aves , Poluentes Químicos da Água/análise
19.
Science ; 379(6636): 972, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36893236

RESUMO

"Mammoth" plan to control a coastal invader would benefit migratory birds.


Assuntos
Aves , Espécies Introduzidas , Animais , China
20.
Sci Rep ; 13(1): 2258, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859497

RESUMO

Animal personalities manifest as consistent individual differences in the performance of specific behavioural expressions. Personality research has implications for zoo animal welfare, as it can further our understanding of how captive individuals may differ in their resource use and provide insight into improving individual and group social health. For group living species, personality may enable assortment based on similar behaviour and influence an individual's interactions with conspecifics (e.g. social support). This research aimed to document how personality traits (aggressive, exploratory, submissive) influenced the social network structure of highly social animals in a captive environment. Data were collected from separate flocks of captive Caribbean (Phoenicopterus ruber) and Chilean flamingos (Phoenicopterus chilensis) to identify relationships between birds and examine opportunities for social support. The flocks associated non-randomly, and in both cases, personality was a substantial predictor of network structure. Personality also predicted key elements of Caribbean flamingo social role (degree, betweenness and average association strength) conflict outcome, and propensity to provide social support, however these patterns were not replicated within the Chilean flamingo network. While both species appear to assort by personality, the broader relationship between personality and social role may vary depending on species and context.


Assuntos
Transtornos da Personalidade , Personalidade , Animais , Individualidade , Aves , Rede Social
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